1. Field of Invention
Every chip needs the clock and the power supply. Therefore, the green chip platform must include both the clock and power supply. The crystal is a mechanical resonator. It takes a lot of energy to drive the mechanical resonator to oscillate. Furthermore, the size of crystal is too large to integrate into the chip package. Therefore, it is ideal to use the electronic resonator to replace the mechanical resonator.
Ideally, the electronic facility should have the better performance than the mechanical facility. Therefore, the electronic resonator should have the better performance than the mechanical resonator. However, for one hundred years, we still use the crystal to be the reference of oscillator. To be miniature, the on-chip MEM was adopted to be the reference. However, after several years of trial, the MEM project almost all fails.
The only survival is the LC resonator. However, the previous approach of the prior art used the frequency controller. It is based on the open-loop free-running oscillator. It suffers the low Q, temperature, humidity and package problem. Since there is no other clock reference. The LC resonance itself is the final reference. It is impossible to measure the frequency deviation to make the frequency correction with feedback control.
Therefore, we make the innovation of VFACO Varactor Free Amplitude Controlled Oscillator to be the MS0-GBQ-AMC LCO. MS0 represents the Moisture Sensitivity level is Zero. The clock frequency is independent of the humidity moisture level to be constant. GBQ represents the Gain-Boost Quality factor Q. AMC is the AMplitude Controller. In contrast to the open-loop free-running frequency controller of the prior art, the Amplitude Controller AMC is a closed-loop feedback control. The frequency is function of the amplitude. f=f(A). We can control the amplitude A of the LC resonance to control the frequency.
The planar-inductor design is the key component of the MS0-GBQ-AMC LCO. MS0 is the component/device GBQ is the circuit level. AMC is the system level. With the innovations in component/device level, circuit level and system level, we make the on-chip Xtaless ClockChip dream come true. With the green-technology, our Xtaless ClockChip has the superior performance: (1) Ultra-High Q Clock Performance and EMI-free (a guided magnetic field flux) inductor or transformer: (2) Since the self-compensation that only the 2nd order variance is left to be the Trimming-less. As the 2nd order is negligible for the low performance clock, it can even be trimming-free to save the cost of test and calibration (3) Plastic-Package-able & IP-able: (4) Ultra-Low Cost (CMOS compatible): (5) It is the only “marketing-ready” real clock “product” design.
The planar-inductor also can apply to the PCB for large power handling capability. The derived products are the versatile sockets and plugs for the green technology. For the safety purpose, the Vialess-ESD-PCB and planar-inductor work together to serve as the platform of the system level green technology. To have the 100% protection for all the signal, each net has to have one via for the ESDS Electrostatic Discharge Switch. There is the requirement to minimize the number of vias. The smart via assignment algorithm is developed to have the global via minimization. Based on our innovative methodology. The algorithm is developed for circular linear placement.
2. Description of Prior Art
In the System-On-Chip SOC technology, all the on-board components are trying to merge into the chip. The components cannot be merged, then new circuits are developed to replace the function of these components. As the component is merged into the chip, it saves power and resource. It meets the requirement and developing trend of the Green Technology.
Every chip needs the power and clock that the clock is the first to be considered merged on-chip. There are many ways to approach this problem. However, all the pioneers still followed the crystal concept that all of them used the MEM to be the reference resonance. However, the MEM approach has many defects of the aging problems, etc. The cost is high. It cannot compete the crystal oscillator, either. Therefore, the MEM approach has died.
So, the MEM clock companies switches to the LC resonator approach. However, they still use the traditional crystal resonator approach. The crystal resonator is free running. You cannot control the crystal lattice resonation. The prior art of LC resonator uses the free-running methodology, too. Therefore, the prior art put a lot effort to improve the quality Q of the inductor and let the LC resonator open-loop free running. This open-loop free-running methodology is named as the frequency control. However, there is no feedback control at all. The methodology just set the parameters for the temperature, then let the LC resonator to have free running. So, it should be named as the frequency-set instead of the frequency control. Their frequency control is actually not frequency control. There is no such function of freq=f(freq). Frequency is the controlled object. It is wrong to use the frequency to control the frequency itself. Controlling the frequency should be based on the other parameters instead of the frequency itself. Therefore, the traditional frequency controller becomes an open-loop free running. There is only parameter set for the frequency. There is no closed-loop feedback control for the frequency control.
Many people can design LC resonator, however, none of them can design the Xtaless Clock. The design of VFACO Varactor Free Amplitude Controlled Oscillator Xtaless Clock is completely different form the design of Voltage Controlled Oscillator VCO type LC resonator. The prior arts use the conventional Voltage Controlled Oscillator VCO type LC resonator design methodologies to design the Xtaless Clock. The Voltage Controlled Oscillator VCO type LC resonator has the essential self-oscillation-induced phase noise problem. It has no way to use as the LCO of the clock chip. This is the essential disaster problem of the Voltage Controlled Oscillator VCO type LC resonator to serve as the clockchip. However, nobody recognized the disaster problem. It causes the phase noise and the performance is 50 ppm over temperature variation. However, the market requirement is 1 ppm. Therefore, the prior arts of VCO type LC resonator clockchips go nowhere. After many years, the prior arts still fail to recognize the essential characteristics of the Xtaless ClockChip.
The integrated LCOs exhibit a substantially linear negative temperature coefficient (TC). To stabilize the TC, a method of the varactor diode is introduced. The capacitance of the varactor diode has the minor variance during the oscillation of the LC oscillator. The minor variance of the capacitance of the varactor diode will generate the serious Close-To-Carrier phase noise problem. Furthermore, the on-chip inductor has low Q factor. The Q factor has the inverse-square relationship with phase noise. Consequently, it is expected that the close-to-carrier (CTC) phase noise of the LCO will be substantially higher than for a comparable XO. This makes the LCO poorly suited to RF applications due to concern over reciprocal mixing and the associated degradation in receiver sensitivity.
Even worse, in the prior art, the resonant frequency varies according to the humidity. As the moisture level changes, the LC resonant frequency changes about 600 pans per million PPM between the Florida and Las Vegas. Therefore, they have to use the ceramic package to walk around the problem. However, it only solves the short-term test problem. It doesn't solve the long-term user problem. In the short-term test, changing the humidity of the test chamber, it doesn't see the problem. However, in the long run of the field application, it still shows the frequency drift due to the humidity moisture change. Even using the ceramic package doesn't solve the humidity moisture level problem, either. However, the prior an still doesn't recognize the moisture sensitivity level problem for the Xtaless ClockChip at all.
What is the difference? the Methodology. In the Elementary School, you use the Arithmetic to solve the problem. In the University, you use the Calculus to solve the same problem. Similarly, the prior art used the undergraduate EE student circuit theory to solve the LC resonator problem. They set the LC parameters and let it free running. They named the set of LC parameters to be frequency control. Actually, there is no control at all. We are able to use the most advanced Circuit and System Design Methodology to solve the LC resonator problem. Why is our approach superior to the prior arts? The simple terms are the “Design Methodology”. With the most advanced Circuit and System Design Methodology, we use the anti-chaos circuit to control the chaotic LC resonator. However, the prior arts use the idealized LC resonator and the prior arts even don't know the real-life LC resonator has the parametric chaos circuit all. They just have the frequency parameter setting. They don't have the frequency control at all. From the functional relation, the frequency control is freq=f(freq). There is no such kind a function. Therefore, the prior arts actually have the frequency parameter setting. The prior arts don't have the frequency control at all. Actually, there is no such kind frequency control for the LC resonator frequency. This term “frequency control” for the LC resonator is completely violating the rigorous analytic methodology and philosophy.
The prior art clock chips are not “marketing-ready product” yet. There is no comparison between the prior Reference-free ClockChip with our Xtaless ClockChip. The prior-art clock chips are not “market-ready product” yet. The prior-art still have far way to go: they have a lot things to learn.
In our approach, we identify the functional relation of the amplitude controlling the frequency in the LC resonator. Then we controlling the amplitude to fix the frequency. The function relation is freq=f(amplitude). From the fundamental knowledge methodology and design philosophy, this amplitude control is a valid approach. However, the frequency control of the prior art is not a valid approach at all. If the fundamental methodology is not correct, how the prior arts can get the correct results? Therefore, the prior arts used the “curve fitting” to fit for the test bench calibration results. There are so many parameters varying over such a long time and different environments. The prior art is a hopeless approach. However, the prior arts don't know the fundamental problem is their design methodology and the architecture and system based on the wrong design methodology, not the circuit itself.
Furthermore, we adopt the green technology platform approach. The Xtaless ClockChip technology can be extended to apply in the inductorless Power Management Unit PMU and the high power efficiency power amplifier. The inductor of the PMU and PA can be implemented with the on-chip planar inductor to be the inductorless PMU and inductorless PA. It saves a lot of energy and resource to be the green chip of the green technology.
Objects and Advantages
The green technology platform is constituted of the clock and power. The power includes the PMU and PA. The clock is the Xtaless ClockChip and the power is the no on board inductor Inductorless PMU and PA. All the Xtaless ClockChip. Inductorless PA and PMU are based on the planar inductor technology. Furthermore, the Xtaless ClockChip adopting the amplitude controller methodology, the Inductorless PMU adopting the ZVS Zero Voltage Switch methodology and the PA using the recycling-energy to have the high performance of the green chip technology platform.
The amplitude control for the Xtaless ClockChip is the closed-loop feedback control having the self-compensation capability. Even we still use the NVM for trimming of the 2nd order effects, it can self-compensate and self-adaptive for the variance of the gain due to the variation of temperature, voltage, aging, etc. With the self-compensation design techniques, only the 2nd order variance effect is left that the Xtaless ClockChip is able to be trimming-less or even trimming-free.
The conventional crystal technology is limited to the low frequency. However, the planar inductor can operate at the high frequency that the resonator technology can be extended to the high frequency operation inductorless PMU and inductorless PA to have the complete set of the green technology platform.